Plaster board



' J. F. HAGGERTY PLASTER BOARD Fild July 25, 1921 TTOF/VE/f I Patented May 26, 1925.

UNITED STATES PATENT OFFICE. 1

JOSEPH F. HAGGERTY, 0F BUFFALO, NEW YORK, ASSIGNOR T0 UNIVERSAL GYPSUM COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE;

PLASTER BOARD.

Application filed July 23, 1921. Seria1 No. 487,004.

To all 107mm if m (13/ concern.-

Be it known that l, Josnrn F. Haoonnrr, a citizen ot the United States, residing at Buffalo, in the county of Erie and State of New York, have invented a new and useful Improvement in Plaster Board, of which the following is a specificatio s This invention relates to improvements in plasterboard of the kind comprising a suitable body oi plastic material provided With a covering of sheets of paper or other fibrous material.

Plasterboard has heretofore-been made both in molds and by continuous method, by machine or: otherwise, in various widths or thicknesses,the plasterboard usually con sisting of plaster of Paris or other suitable plastic material which is covered with a fibrous material,.such'tor example as paper. This covering is arranged on the opposite sides or faces of the board and in some cases the edges of the board are also covered. In the case of plasterboard not having the edges covered, considerable difliculty is experienced, due to the fact that the core or plastic filler, when dry chips out when handled at the factory, while being: shipped. and while being erected. l 'urthern'iore, the dry core, owing to its brittlcness. easily chips out when being: nailed,

especially since the nailingordinarily must be done near the edges of the board. In the case of plasterboard now on the market having its opposite edges covered with fibrous material, the adjacent edges of the' covering material overlie each other and are bold together'by such portions of the tiller or plastic material as squeezes or flows be-' tween the two edges Board of this type is objectionable because the layer of, plastic material between the two edges is very thin and being); brittle,.is easily brokenand falls out, weakening the board at this point, and

furthermore, it frequently happens that the plastic material does not How or squeeze out far enough to secure the edges of the cov-' lll'lnfl material together.

The objects of this invention are to proide a plasterboard of this kind in which the covering material is so arranged as to greatly reinforceor strengthen the edge portions of the plasterboard and protect the same against injury; also to provide improved and hard\ easily breaks or as shown at l) to means for sealing together the edge portions of the sheets 0t fibrous material also to im prove plasterboard of this kind in the other res ects hereinafter specified.

bodiment of the invention shown in the drawings; Each of these sheets covers a face of the board and extends around the edges thereof and along the marginal portionsof the opposite face, the two sheets overlapping at the edge portions of the board in such a manner that these portions of the board will be'covered by a double thickness, or two layers of paper or fibrous material. In the construct-ion shown in the drawings, the

sheet B covers one face of the board and-the opposite sides of the sheet are folded over board and to cover the edge or margin portions of the opposite face of .the board as shown at 7;. The covering;- sheet C covers the opposite face of the board and the sides of this covering sheet extend around the (l'lhl of the board, overlying, or covering the edge or side portions of the sheet B. The port ions- 0 of the covering sheet extend around the edges of the board and the extreme c sc por tions 0 of the coverine sheet extend to the face of the board opposite to the face covered by the body portion of the covering sheet. \Vhen the board is pressed by any suitable or usual 1neans,the edge portions 0 of the covering sheet are preferably depressed into the face of the board so that these edge. portions "same plane as the body portion of the sheet The sheets of fibrous material are prefers y v ably placed into contact the same is wet, on

w'vithfih'e core, while i lzjvlafitlc condition. so

enclose the edges of the- V 100 lie substantially in the.

LIX

that all parts of the sheets contacting" with the core are secured thereto when the hoard is dried. In order to reinforce the edges of the hoard, however, the portions of the two sheets which overlap one another or preferably placed into Contact so that none oi the plastic nniterial cnte between the contacting portions of the two sheets, and these portions of the sheets are secured together by means suitable g'lueor adhesi For this purpose water-proof or watenresisting adhesive, such for example as a solution of casein has been found entirely satisfactory, although obviously many other substances, such as silicate of soda, animal glue or other materials may he used. Fig, 3 shows how my improved board is secured to studdingD, to wit, by means of nails or the like (Z which pass through four thicknesses of paper or fibrous covering material.

" By making the hoard as described, it will be seen that our thicknesses of fibrous meterial are provided at the point Where the edge is nailed, which heretofore has been the Weakest part of the board or panel. Since the fibrous material is very much. tougher than the core of the board, damage to the board by breaking or chipping of the edges t-hcreof is largely prevented. of the edge portions of the board is further increased by gluing or pasting together the two layers or thicknesses of paper by means of a tough and elastic adhesive instead of using the brittle plastic material for the purpose of securing these edge portions together, as has heretofore been done. Those skilled in the art recognize that the greater part of the strength of plasterboard is in the.

paper covering, so that it is obvious that my improved board has very much stronger edge portions than those heretofore made, especially since the adhesive used, has a strengthequal to or in excess of the fiber strength of the covering); material and very much greater than that of the plaster of Paris 'now used for the purpose of securing together the edges of the fibrous covering material. The double thickness of covering material also protects the board against injury while being handled and shipped.

While the particular arrangement of the sheets of covering material relatively to each other and to the plasterboard as described desirable, yet it is not intended to limit the invention to this arrangement The strength the sheets, since obviously other arrangements niey ho used to produce platerbonrd having reinl'orccd edge portions as described.

l claim as in invent-loin l. :r plasterboard comprising a body made of plastic material, a sheet of fibrous niaterisl secured to each face oi" said body portion one of said sheets having its edge portions extending around the opposite edges of said body and along the margins of. the opposite lace, and the other sheet having its edge portions overlapping the portions of said mentioned sheet and extending arc-mid the edges of the board and along the margins of the race covered by said To first.mentioned. sheet, said overlapping edge portions being secured together by an adhesive, whereby the edges and margins of said board are covered by a double thickness oi fibrous material.

2, A plasterboard comprising a body made of plastic material, a sheet or fibrous covering material secured to each face of said body portion, each of said sheets of covering material having its n'iarginal portions ere tending around the opposite edges of said body and over onto the marginal portions of the opposite faces of said body and overlapping the corresponding marginal por- 'tions of the other sheet, to cover the opposite edges and marginal portions of said body With a plurality o'fithicknesscs of covering materiel.

3. A plasterboard comprising a body made of plastic n'iaterial, a sheet of fibrous covering materiel secured to each face or said body portion, each of said sheets ofcov'ering material having its marginal portions extending around the opposite edges ot ssiol body and over onto the marginal pore5 tions of the opposite oil? said body ainL overlapping the crn'responding nniro iuii portions oi. the other sheet, the overlapping portions of said covering material being so cifrcd together by an adhesive.

4. A plaster \vallboard having a composition body with fibrous cover sheets i lwlifllh one of said, cover shoots passing about lhe longitudinal edges of the o'ullboard lo cu gage the opposite side thereof with the other cover sheet extending beyond the side it covers and with its margins secured to first sneot and their exterior surfaces in the plane of the surface they engage.

JOSEPH F. ll} (ltlldlllY. 

